<template>
  <div class="login-container">
    <div class="login-box">
      <!-- 头像区域 -->
      <div class="avatar">
        <img src="../assets/logo1.png">
      </div>
      <!-- 登录表单区域 -->
      <el-form ref="loginFormRef" :model="loginForm" :rules="loginFormRules" label-width="0px" class="login-form">
        <!-- 用户名 -->
        <el-form-item prop="username">
          <el-input v-model="loginForm.username" prefix-icon="iconfont icon-user"></el-input>
        </el-form-item>
        <!-- 密码 -->
        <el-form-item prop="password">
          <el-input v-model="loginForm.password" prefix-icon="iconfont icon-3702mima" type="password"></el-input>
        </el-form-item>
        <!-- 按钮区域 -->
        <el-form-item class="btns">
          <el-button type="primary" @click="login">登录</el-button>
          <el-button type="info" @click="resetLoginForm">重置</el-button>
        </el-form-item>
      </el-form>
    </div>
  </div>
</template>

<script>
export default {
  data() {
    return {
      // 登录表单的数据绑定对象
      loginForm: {
        username: 'admin',
        password: '123456'
      },
      // 登录表单的验证规则对象
      loginFormRules: {
        // 用户名的校验规则，验证用户名是否合法
        // 文本框失去焦点时，触发此验证行为
        username: [
          { required: true, message: '请输入登录名称', trigger: 'blur' },
          { min: 3, max: 10, message: '长度在 3 到 10 个字符', trigger: 'blur' }
        ],
        // 密码的校验规则，验证密码是否合法
        password: [
          { required: true, message: '请输入密码', trigger: 'blur' },
          { min: 6, max: 15, message: '长度在 6 到 15 个字符', trigger: 'blur' }
        ]
      }
    }
  },
  methods: {
    // 点击重置按钮，重置登录表单
    resetLoginForm() {
      this.$refs.loginFormRef.resetFields()
    },
    login() {
      // 登录前表单预验证
      this.$refs.loginFormRef.validate(async valid => {
        if (!valid) return
        const { data: res } = await this.$http.post('login', this.loginForm)
        if (res.meta.status !== 200) return this.$message.error('登录失败')
        this.$message.success('登录成功')
        // 1.将登录成功之后的 token 保存到客户端的 sessionStorage 中
        window.sessionStorage.setItem('token', res.data.token)
        // 2.通过编程式导航跳转到后台主页
        this.$router.push('/home')
      })
    }
  }
}
</script>

<style lang="less" scoped>
  .login-container {
    background-color: #2F4F6F;
    height: 100%;

    .login-box {
      width: 450px;
      height: 300px;
      background-color: #fff;
      position: absolute;
      top: 50%;
      left: 50%;
      transform: translate(-50%, -50%);
      border-radius: 3px;

      .avatar {
        width: 130px;
        height: 130px;
        border: 1px solid #eee;
        border-radius: 50%;
        padding: 8px;
        box-shadow: 0 0 8px #ddd;
        position: absolute;
        left: 50%;
        transform: translate(-50%, -50%);
        background-color: #fff;
        img {
          width: 100%;
          height: 100%;
          border-radius: 50%;
          background-color: #eee;
        }
      }
    }
  }

  .login-form {
    position: absolute;
    bottom: 0;
    width: 100%;
    box-sizing: border-box;
    padding: 0 20px;
    .btns {
      display: flex;
      justify-content: flex-end;
    }
  }
</style>
